This invention relates to casting electrically conductive, molten materials and, more particularly, to a method and apparatus for determining the flow pattern of the casting charge of a molten, electrically conductive, molten material as it fills a mold cavity.
For some metal casting operation, it is desirable to have an inexpensive method and apparatus for determining the effect different process variables have on the flow pattern of the molten metal as it fills the mold cavity. This is particularly true for so-called lost foam casting processes in which the mold cavity is formed by a pattern in the shape of a cast part and made from a material, such as polystyrene, which is vaporized upon being contacted by the molten metal. These vapors are diffused into a porous material, such as sand, surrounding the pattern. Consequently, a test mold made from a substantially impervious, transparent material, such as quartz glass, can not be used to study the flow pattern of the molten metal in such a process.
Heretofore, high powered X-ray films, infrared pictures and devices employing thermocouples have been used for this purpose. These prior techniques and devices generally require relatively highly skilled personnel, are quite expensive, and/or provide results which can be easily misinterpreted.
Attention is directed to the following United States patents:
______________________________________ Patentee U.S. Pat. No. Issue Date ______________________________________ Heimgartner 3,537,295 Nov. 3, 1970 Slamar 3,893,502 July 8, 1975 Terkelsen 3,931,847 Jan. 13, 1976 Carbonnel 4,213,494 July 22, 1980 ______________________________________